The annual CrossFit Games are coming to a ringing and controversial close this weekend with the awarding of Glock handguns to the winners. But CrossFit, Inc. received something else on Friday—a potentially devastating blow in the lawsuit it brought against the founders and creators of CrossFit Kids, Jeff and Mikki Martin.

Early Friday morning, the Martins filed a Rule 11 motion in US District Court in Arizona, asking the court to dismiss CrossFit’s complaint against them for trademark infringement, and seeking $225,000 in attorneys’ fees against both CrossFit and its attorneys for pursuing frivolous claims. The Martins' motion is here; the exhibits are here.

In 2004, the Martins turned their local gym in Ramona, California into one of the first CrossFit affiliates. CrossFit’s CEO, Greg Glassman, testified last spring that within months, CrossFit had granted the Martins a license to develop the CrossFit Kids seminars. Over the coming years, the Martins built a complete youth training methodology and business, launching the crossfitkids.com website, developing training seminars, creating lesson plans, and offering CrossFit Kids affiliations to existing CrossFit affiliates.

At CrossFit’s request, and based on promises of profit-sharing, the Martins became employees of CrossFit in 2011 and continued to run the CrossFit Kids program, though they became increasingly marginalized. In March 2014, CrossFit suddenly demanded that the Martins hand over control of the crossfitkids.com website they owned and created, and told them that they had no right to use the CrossFit Kids name. After a few months of start-and-stop negotiations, on October 14, 2014 CrossFit abruptly fired the Martins and sued them for trademark infringement—even though, as Glassman testified, the Martins’ license to use the CrossFit Kids name was never terminated. Dismayed by their treatment and CrossFit’s mishandling of youth programs, in February 2015 the Martins gave up the CrossFit Kids name, and in May 2015 handed over control of the crossfitkids.com website. More than a year later, CrossFit has still put no content on that website, undermining its claim that it sued the Martins to prevent “cybersquatting.”

In their Rule 11 motion, the Martins describe not only these basic flaws with CrossFit’s trademark claims, but also the company’s campaign of harassment against them, including telling the Martins’ children, who still worked at CrossFit, not to publicly associate with their parents' new company, threatening to sue one of the Martins' sons for a single joking Facebook post that used the hashtag #crossfit (there are some 18 million posts on Instagram using that same hashtag, many of them trying to profit off the mark), and publicly disclosing their private settlement negotiations.

The Martins are represented by Christopher Wimmer and Peter Roldan of San Francisco and New York law firm Emergent, PC. “Greg Glassman has likened his company to a ‘biker gang,’ and the motion accuses CrossFit of ganglike behavior—trying to bludgeon the Martins into submission with expensive litigation even though the company knows it gave the Martins permission to develop CrossFit Kids and never revoked it. We are hopeful the court will see through CrossFit’s behavior and sanction the company and its counsel by throwing out the lawsuit against the Martins,” said Mr. Wimmer.

The Martins' new business, The Brand X Method, offers a comprehensive, next-generation fitness framework designed to deliver physical literacy over the life course, preventing injuries, improving sports performance, and keeping people active and engaged for a lifetime. As their website prominently advertises, they are no longer associated with CrossFit.